Tube-making method and apparatus



H. L. YOUNG TUBE MAKING METHOD AND APPARATUS Ju'ne 16, 1931.

2 Sheets-SIl-et l Filed July 2'7, 1928 H. l.. YOUNG TUBE MAKING METHOD AND APPARATUS Filed July .27, 1928 2 sheets-sheer 2 y 99m/Qa @y a June 16, 1931.

Mmmm@ tsiass OFFICE H if. L. YOUNG, OF ON, OHIO, ASSIGNOR TO THE B. F. GOODRIGH COMPANY, 0F l NEW YORK, N. Y., .A CORPORATION OF NEW YORK TUBE-M :t

` .t TUS rlhis invention relates to the art of making rubber tubes by longitudinally feeding a continuous strip of sheet-ed'rubber stock and progressively folding the margins of the strip into contact with each other and joining them v tofore known.

in a seam to g1ve the strip tubular form.

The chief object of the invention is to provide an improved method and improved apparatus for folding the marginal portions of a Hat strip of material into overlapped relation and joining them in a smooth, strong and imperviouslongitudinal seam. Another oba embodying and ject is to reduce the friction of the strip in contact with the tube-forming apparatus. Another object is to provide for forming the tube progressively from a continuous strip of rubber drawn, in av soft and tacky condition, directly from a calender, and thus to avoid the expense of liners, storage, and trucking. A furtherjobject is to produce tubeswhichare uniformly of correct diameter.

Of the accompanying drawings:

Fig. 1 is a perspective view of apparatus adapted to carry out my in vention in its preferred form.

Fig. 2 is a fragmentary transverse section of the work through the longitudinal seam thereof as the latter is initially formed.

4 Fig.h3 is a view similar to Fig. 2 at a subsequent lperiod of operation showing the seam in its final coalesced or healed condition.

Fig. 4 is a plan vview of a portion of the y' apparatus shown in Fig. 1, parts being broken away and in section. v

Fig. 5 is a vertical section of the apparatus shown in Fig'. 4,'appart being. broken away and in section.

Fig. 6 is a section on line 6-6 of Fig. 4. Fig.,7 is a'section on line 7-7 of Fig. 4. v Referring to Fig. 1 of the drawings, 1() -is an endless conveyor belt upon which a strip of unvulcanized rubber composition 11 is delivered to and conveyed from my improved'tubaforming apparatus. Preferably the stripV 11 is drawn continuously through my folding and seaming apparatus from the calender on which it is formed. The strip 11 preferably has stepped marginal portions 11, 11" of diminishing thickness toward their edges as shown, obtained by sheeting two strips of stock and assembling them, as they pass from the calender, in face-to-face contact with each other with their margins offset, in a manner here- Spanning the conveyor belt 10 just above the upper reach thereof is a table 12 upon which are mounted an inclined strip-guide 13, a strip-folding device 14, anda seamcoalescing device 15. A strip-guiding and supporting roller 16 is j ournaled at the workreceiving end of the inclined strip-guide 13, and the latter is adapted to receive the strip 11 as it is drawn upward olf the conveyor v10, and to direct it in a descending path toward the receiving end of the strip-folding device-14. v

and this construction may be The strip-folding device is adapted to fold Y the marginal portions of the strip 11 onto each other and join them in alongitudinal seam. It comprises a hollow cylindrical axial form or mandrel 17 and a pair of concentric, j

transversely-arcuate, hollow sleeve-members 18, l18x extending about said axial form at :the respective sidesv thereof and radially spaced therefrom so as to define therewith a stock-receiving space. The mandrel 17 is supported in horizontal position from above, being formed with a boss 17 which is secured by screws 17 b, 17b to an overhanging bracketarm 19 mounted upon the table 12.

Each sleeve-member 18, 18x is provided at its lower margin adjacent its ends with respective hinge-members 20, 20 and the hinge members of both sleeves are vpivoted in axial alignment at 2l, 21 upon respective brackets 22, 22 mounted upon the table 12; Each sleeve member is provided with a downward-V ly-extending arm 23 and said arms are connected to each lying beneath the above theaxis of the pivots 21, the arrangement being such that theasleeves are yieldingly held normally in closedl or operative other by a tension spring 24v j sleeves and normally j position, but may be held in opened position,

with the spr1ng24 in over-center position with relation to the axes 21, upon occasion,

as when the leading" end of the strip 11i's initially threaded through the folder. Arms 25, 25 extending up-ward from the respective sleeve-members 18, 18x have their respective end-portions provided with; set-screws 26, 26 which bear against opposite sides of the seam-coalescing device 15 when the sleeve members are in operative position, to position said sleeve-members and to provide adjustment to compensate for slight variation in the thickness of the strip 11.

The folding of the strip 11 and the overlap-ping of its marginal portions in the folding device 14:.is effected with desirable accuracy by reason of the shape of the upper margins of the sleeve members 18, 18* which define a. stripsguiding bight, the design of which is best, shown in Figs. 1 and 4. The upper margins 18a, 18b of the sleeve-members 18, 18x recede from the work-receiving end of the device in helicoidal curves and the margin 18b is of lesser pitch than the margin 18'2l Where they approach each other at the upper, middle zone of the device, and from an approximately medial position7V in said zone the margin 18h, Fig. L1, continues in .a reach 18c transverse to its helicoidal reach and uniformly spaced from the margin 18a and then in a semi-circular reach 18d and a return reach 18e, the latter lying in extension of the margin 18a, so that the reaches 189, 18d, 18e of the margin 18b and the adjacent part of the margin 18a define in effect a closed-end slot which accommodates and Whose walls suitably guide thev margins 11a, 11b of the laminated strip 11.

A plow 27 is mounted upon the boss 17a vof the mandrel 17 and extends toward the -point where the converging margins 18a, 18", of the sleeves 18, 18", approach nearest each other, the plow 27 being adapted to hold the overlying margin 11b of the strip 11 out of contact with the underlying margin 11a thereof until both margins are properly positioned one above the other. The overlapped marginal portions of the laminated strip 11 are shown in Fig. 2 and the tubular structure thus formed is designated 28.

\ To avoid excessive friction between the mandrel 17 and the strip 11 as the latter is drawn throughthe folding device, the mandrel 17 is formed with a plurality of apertures 29, 29 extending throu h its top wall adjacent the delivery end t ereof and the hollow interior of the mandrel is "connected with a source of pressure Huid through a supplyfpipe 30 mounted in the end wall of the mandrel at the receiving end thereof.

Also for air-lubrication the sleeve-members 18, 18 have their inner walls formed with apertures 31, 3l in their lowermost portions and the hollow interiors of said members are vide the seam-hammering device 15 which comprises two hammers 33, 33 which are positioned in 'longitudinal alignment over the middle zone of the mandrel over which the tube seam is drawn, and the sleeve-members 18, 18x are cut away at 18f, 18f to expose the seam to the hammers at their delivery ends. The hammers 33 preferably are of the pneu'- matic type, as shown, being mounted in respective double-actin fluid-pressure cylinder s, such as the cylinder 34, Fig. 7, of a cylinder-block 35, and actuated by fluid-pressure from pressure lines such as that shown at 36. rIfhe arrangement of inlet and exhaust ports for the cylinders 34 is well known and will be understood from the drawing without further description. The cylinderblock 35 is supported from an overhanging bracket 37 mounted upon the table 12.

The hammers 83 preferably are adapted for such rapid reciprocation as to provide for an overlapping of the areas of the seam which are compacted by successive blows and as to permit substantially uninterrupted movement of the tube through the folding and hammering device at a speed equal to the speed at which thel strip 11 is delivered from the calender.

In the operation of the apparatus, the twoply strip 11 is continuously delivered,l preferably from a' calender, onto the conveyor 10 and then is withdrawn therefrom as the latter passes under the table 12, the strip passing upward overthe guide-roller 16 and downwardly over the strip-guide 13, and then passp ing to the folding device 14 where its lateral marginal portions are folded onto each other. The downward inclination of the stri as it approaches the folding device provi es for folding the flat strip to tubular form without excessive stretching of the marginal por-v tions of the strip, the strip assuming tubular form' by progressive descent of its middle zone with the latter supported by the guide 13 and the margins taking approximately the shortest course from the roll 16 to their positions within the folder, distorting hammock-like support of the freshfsoft stock being largely avoided by the continuing local support of the guide 13.

The strip is folded accurately to size vby reason of the close engagement of the andrel 17 and folding sleeves 18, 18x with both broad surfaces ofthe strip, and friction between the strip and folding mechanism is substantially reduced by reason of the air currents, at low pressure, issuing from the manis compacted and coalesced, the tube 28 passes-K onto the conveyor 12, and thereafter may be cut into lengths suitable for the making 'of inner tubes for pneumatic tires, or otherwise treated.

Friction of the work with the folding device is so reduced by the air currents therein that the friction between the tube 28 and the conveyor 10 is sufficient to draw the work through the aforesaid devices.

The invention provides a rapid and continuous method of making longitudinallyseamed laminated rubber tubing of superior quality and accurate size. The use of closefitting forming mechanism on both surfaces ofthe strip material insures accurate dimensions in the tube, and the avoidance ofv friction in said mechanism obviates stretching of the stock with consequent thinning of the tube-walls.

rlhe tube is made from warm, freshly-calendered stock so that no treatment such as applying a solvent or an adhesive to the margins of the strip is necessary to obtain a strong bond between the margins when they are lapped together, and the bond is further strengthened in .being coalesced by the impact of the hammer blows whereby a smooth and attractive seam is produced.

My invention may be variously modified and l do not limit my claims wholly to the specific construction shown or the exact procedure described.

l claim:-

` 1. The method of lmaking a rubber tube which comprises progressively folding a strip of unvulcanized rubber to tubularform by drawing it through a folder and lubricating with a gaseous fluid applied to the outer face rof the strip the passage of the strip through the folder.

2. The method of making a rubber tube which comprises progressively foldin a strip of unvulcaniz'ed rubber into tubular orm by guidin contact with both faces of the strip and lu ricating with a gaseous fluid the guiding contact of both of the said faces.

3. The method of making a rubber tube which comprises wrapping a strip of material abouta form and folding'themarginal portionsv of the strip into overlapped relation thereupon by progression lengthwise of the strip andcompacting the seam thus formed by pressing it against said form.

4. A method as defined in claim 3 in which the seam is pressed 'against the form by hammering.

y5. Tube-making' apparatus comprising means for folding a strip of material into tubular form and means for directing pressure fluid between the strip and said folding means.

6. Tube-making apparatus comprising means for folding a strip of material -to tubular form by guiding contact with both of its faces and-means `or lubricating with a gaseous fluid the guiding contact of both of the said faces.

7 Tube-making apparatus comprising a stationary mandrel, means for Y'drawing a strip of material past said mandrel, and means for folding said strip around said mandrel and joining its margins in a lapped seam by progression as itis so drawn, said means including a tubular forming structure having strip-guiding margins defining a biglit for lapping one of the margins of the strip upon the other.

8. rl`ubemaking apparatus comprising an apertured, stationary mandrel, means for drawing a strip of material past said mandrel, an arcuate, apertured folding member for folding the strip about the mandrel as it is so drawn, and means for forcing pressure iiuid through the apertures 'of the mandrel and folding member-to lubricate the passage of the strip.

9. Tube-making apparatus comprising a rigidly-mounted, stationary mandrel, means for drawing a strip of material past said mandrel, means for folding the strip about'the mandrel and joining its margins in a seam by progression as it is so drawn, and means cooperatively associated with said mandrel for compacting said seam.

10. rTube-making apparatus as deiined in claim 9 in which the seam-oompactng means 4is a hammer acting against the mandrel as an 1l. rlube-making apparatus comprising a rigidly-mounted, stationary, cylindrical mandrel having a flattened portion, means for drawing a strip of material past said mandrel, folder members for folding the strip I about the mandrel and joining its margins in Y a seam by progression as it is so drawn, and a hammer adapted to deliver repeated blows upon said seam withthe at portion of the mandrel serving as an anvil.

l12. Tube-making apparatus as dened inl claim 11 in which portions of the mandrel and yfolder members are apertured, and in# l cluding means for forcing a fluid through said apertures against the strip.

13. Tube-making apparatus comprisin a stationary, cylindrical mandrel, means l(for drawing a strip of material past said mandrel, and atubular folder formed with strip# guiding margins defininga'bight and extend ing concentrically about said mandrel and adapted to fold the strip and join its margins in a longitudinal lapped seam as it is so drawn.

14. rluloe-making apparatus comprising a stationary mandrel, means for drawing a strip of material `past said mandrel, Aand a.

tubular folder associated with Isaid mandrel and formed with a helicoidal folding edge.

15. rlube-making apparatus as dened in claim 14 in which the folder comprises two cooperating parts each of which has a helicoidal folding edge, said folding edges being of opposite pitch, for folding the strip of material about the mandrel progressively in both transverse. directions from its middle portion.

- 16. Tube-making apparatus comprising a stationary mandrel, means for drawing a strip of stock past said mandrel,means for folding said striparound said mandrel and joining its margins in a seam by progression as it is so drawn, and means for holdmg said margins out of Contact with each other until they are properly positloned one over the other.

17. Tube-making apparatus comprising a stationary mandrel, means for Vdrawing a strip of stock past said mandrel, a pair of folder members formed with respective heli coidal edges of opposite pitch for folding the strip about the mandrel and directing its marginal portions` progressively in helical paths to a' position .where they overlie each other, and a plow member so positioned with relation to the helicoidal folder-edges as 'to hold said marginal portions of the strip out of contact with each other until they are properly positioned with relation tov each other.

In witness whereof I have hereunto set my hand this 23rd day of July, 1928.

` HARVEY L. YOUNG. 

